1. Field of the Invention
The present invention relates to a counterweight device for a construction machine, which detachably mounts a counterweight at a body frame.
2. Description of Related Art
A counterweight is mounted at the rear end of the body frame of a construction machine such as a crawler crane so as to achieve balanced weight distribution during operations. When the crawler crane is transported on a trailer, the counterweight may need to be disengaged from the crawler crane due to restrictions such as the maximum load capacity of the trailer and, in such a case, a counterweight detaching operation must be performed. Japanese Laid Open Patent Publication No. 2000-72383 discloses a counterweight device used in attaching/detaching operations, which includes a pin projecting at a side surface of the counterweight to be engaged at an engaging groove at the body frame. After the pin is engaged at the engaging groove, the counterweight is made to swing along the forward/rearward direction with the pin working as the fulcrum, a spacer is inserted between the front surface of the counterweight and the rear end surface of the body frame and the attitude of the mounted counterweight (e.g., the gap between the counterweight and the body frame) is adjusted.
However, the counterweight device disclosed in the publication mentioned above necessitates the adjustment of the counterweight mounting attitude by inserting a spacer between the counterweight and the body frame when mounting the counterweight, making the mounting operation a laborious process.